python之协程

# 顺序执行
import time

def f1():
    res = 1
    for i in range(100000):
        res +=1

def f2():
    res = 1
    for i in range(100000):
        res *=i

start = time.time()
f1()
f2()
stop = time.time
print("run time is %s" % (stop - start)

切换

from greenlet import greenlet
import time

def f1():
    res = 1
    for i in range(1000000):
        res +=1
        g2.switch()

def f2():
    res = 1
    for i in range(1000000):
        res *= i
        g1.switch()

start = time.time()
g1 = greenlet(f1)
g2 = greenlet(f2)
g1.switch()
stop = time.time()
print("run time is %s" %(stop - start)

        

import gevent

def eat(name):
    print("%s eat 1" % name)
    gevent.sleep(2)
    print("%s eat 2" % name)

def play(name):
    print("%s play 1" % name)
    gevent.sleep(1)
    print("%s play 2" % name)

g1 = gevent.spawn(eat,"egon")
g2 = gevent.spawn(play,name = "egon")

g1.join()
g2.join()

#或者gevent.joinall([g1,g2])
print("主线程结束")

from gevent import spawn,joinall,monkey;monkey.path_all()

import time

def task(pid):
    ‘‘‘Some non-deterministic task‘‘‘
    time.sleep(0.5)
    print("Task %s done" % pid)

def synchronous():
    for i in range(10):
        task(i)

def asynchronous():
    g_l=[spawn(task,i) for i in range(10)]
    joinall(g_l)

if __name__ == ‘__main__‘:
    print(‘Synchronous:‘)
    synchronous()

    print(‘Asynchronous:‘)
    asynchronous()
#上面程序的重要部分是将task函数封装到Greenlet内部线程的gevent.spawn.初始化的greenlet列表存放在数组threads中,此数组被传给gevent.joinall 函数,后者阻塞当前流程,并执行所有给定的greenlet.执行流程只会在所有greenlet执行完后才会继续向下走.

from gevent import monkey;monkey.patch_all()
import gevent
import requests
import time

def get_page(url):
    print(‘GET: %s‘ %url)
    response=requests.get(url)
    if response.status_code == 200:
        print(‘%d bytes received from %s‘ %(len(response.text),url))


start_time=time.time()
gevent.joinall([
    gevent.spawn(get_page,‘https://www.python.org/‘),
    gevent.spawn(get_page,‘https://www.yahoo.com/‘),
    gevent.spawn(get_page,‘https://github.com/‘),
])
stop_time=time.time()
print(‘run time is %s‘ %(stop_time-start_time))

from gevent import monkey;monkey.patch_all()
from socket import *
import gevent

#如果不想用money.patch_all()打补丁,可以用gevent自带的socket
# from gevent import socket
# s=socket.socket()

def server(server_ip,port):
    s=socket(AF_INET,SOCK_STREAM)
    s.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
    s.bind((server_ip,port))
    s.listen(5)
    while True:
        conn,addr=s.accept()
        gevent.spawn(talk,conn,addr)

def talk(conn,addr):
    try:
        while True:
            res=conn.recv(1024)
            print(‘client %s:%s msg: %s‘ %(addr[0],addr[1],res))
            conn.send(res.upper())
    except Exception as e:
        print(e)
    finally:
        conn.close()

if __name__ == ‘__main__‘:
    server(‘127.0.0.1‘,8080)

服务端

服务端

#_*_coding:utf-8_*_
__author__ = ‘Linhaifeng‘

from socket import *

client=socket(AF_INET,SOCK_STREAM)
client.connect((‘127.0.0.1‘,8080))


while True:
    msg=input(‘>>: ‘).strip()
    if not msg:continue

    client.send(msg.encode(‘utf-8‘))
    msg=client.recv(1024)
    print(msg.decode(‘utf-8‘))

客户端

from threading import Thread
from socket import *
import threading

def client(server_ip,port):
    c=socket(AF_INET,SOCK_STREAM) #套接字对象一定要加到函数内，即局部名称空间内，放在函数外则被所有线程共享，则大家公用一个套接字对象，那么客户端端口永远一样了
    c.connect((server_ip,port))

    count=0
    while True:
        c.send((‘%s say hello %s‘ %(threading.current_thread().getName(),count)).encode(‘utf-8‘))
        msg=c.recv(1024)
        print(msg.decode(‘utf-8‘))
        count+=1
if __name__ == ‘__main__‘:
    for i in range(500):
        t=Thread(target=client,args=(‘127.0.0.1‘,8080))
        t.start()

多线程并发多个客户端，去请求上面的服务端是没问题的